I’ve mentioned a couple of projects for working with UIColor such as the ColorUtil library that provides a number of helper methods for working with UIColor and the ColorSense Xcode extension that provides a color picker when working with UIColor in Objective-C within Xcode.

Here’s another project for working with UIColor called Colours For iOS from Ben Gordon.

Colours for iOS provides over 100 predefined UIColors that you can call using their predefined text names, along with helper methods allowing you to work with color hex values, and for gathering the RGBA values of any color.

You can also create color schemes from a UIColor.

Here are a couple of images showing the included example application in action: